The catch is you need to practice it for 6 weeks. I imagine that's every night for 6 weeks.

"The US Navy Pre-Flight School developed a scientific method to fall asleep day or night, in any conditions, in under two minutes," the book reads.

"After six weeks of practice, 96 percent of pilots could fall asleep in two minutes or less. Even after drinking coffee, with machine gunfire being played in the background."

Here's how to do it:

Relax the muscles in your face, including tongue, jaw and the muscles around the eyes
Drop your shoulders as far down as they'll go, followed by your upper and lower arm, one side at a time
Breathe out, relaxing your chest followed by your legs, starting from the thighs and working down
You should then spend 10 seconds trying to clear your mind before thinking about one of the three following images:

You're lying in a canoe on a calm lake with nothing but a clear blue sky above you
You're lying in a black velvet hammock in a pitch-black room
You say "don't think, don't think, don't think" to yourself over and over for about 10 seconds

I've got an alternative method, but it implies having a heavy week at work, sleeping only a little from Friday to Saturday because you're excited, packing your stuff and driving Saturday morning, hiking or playing airsoft for the entire day, not sleeping because you talk with friends (or because some douche in a nearby tent blasts terrible music and yells with his drunk friends), playing or hiking on Sunday, driving home and reaching your bed. I can guarantee you that you'll fall asleep within a minute!

However, the previous build-up isn't that practical and for some reason you can't do that everyday. But then, you can always find on youtube or something a documentary video, choose it with the topic that you're the least interested in, choose a speaker with the most monotonous drone of a voice you can find, and it'll do the trick.

Alternatively, I can make my wife fall asleep within 2 minutes by petting her head and whistling this :

1. Exhale completely through your mouth, making a whoosh sound.
2. Close your mouth and inhale quietly through your nose to a mental count of four.
3. Hold your breath for a count of seven.
4. Exhale completely through your mouth, making a whoosh sound to a count of eight. This is one breath.
5. Now inhale again and repeat the cycle three more times for a total of four breaths.

Generally does work, I've had a few times where it didn't. But I'm going to give yours a go this week!